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Background As syndromic short stature and overgrowth are heterogeneous and the list of causative genes is rapidly expanding, there is an unmet need for identifying genetic causes based on conventional gene testing or karyotyping. Early diagnosis leads to the proper management of the patient and providing genetic counseling for family members at risk in a timely manner. Materials and Methods We conducted targeted exome sequencing to identify the genetic causes of undiagnosed syndromic short stature or overgrowth in 15 pediatric patients from 13 families in Korea. We applied targeted exome sequencing using the Next Seq platform and a TruSight One panel. Results Among the 13 families, 6 different disorders in 8 patients with short stature or overgrowth were identified, and the diagnostic yield was 46.2%. One boy with overgrowth had a TGFB3 gene mutation. In the short stature group, Coffin-Lowry syndrome ( CLS), trichorhinophalangeal syndrome, DYRK1A haploinsufficiency syndrome, short stature with optic atrophy and Pelger-Huët anomaly syndrome with recurrent hepatitis, and type 4 Meier-Gorlin syndrome were identified. One CLS patient had a co-existing monogenic disease, congenital glaucoma, caused by the compound heterozygote mutations of the CYP1B1 gene. Conclusion Targeted exome sequencing is a powerful method for diagnosing syndromic growth disorders. It enables us to understand molecular pathophysiology and investigate new treatments for growth disorders. [ABSTRACT FROM AUTHOR]

Kabuki syndrome (KS) (OMIM#147920) is a multiple congenital anomaly/mental retardation syndrome. Recently, pathogenic variants in KMT2D and KDM6A were identified as the causes of KS in 55.8-80.0% of patients. To elucidate further the molecular characteristics of Korean patients with KS, we screened a cohort of patients with clinically defined KS for mutations in KMT2D and KDM6A. Whole-exome sequencing and direct sequencing for validation were performed in 12 patients with a clinical suspicion of KS. KMT2D and KDM6A mutations were identified in 11 (91.7%) patients. No recurrent mutation was observed, and 10 out of the 11 mutations found were novel. KMT2D mutations were detected in 10 patients, including four small deletions or insertions and four nonsense and two missense mutations. One girl had a novel splice-site mutation in KDM6A. Each patient had a unique individual mutation. This is the first report of mutational analysis via exome sequencing in Korean patients with KS. Because the mutation-detection rate was high in this study, rigorous mutation analysis of KMT2D and KDM6A may be an important tool for the early diagnosis and genetic counseling of Korean patients with KS. [ABSTRACT FROM AUTHOR]

Abstract: Background: Melkersson–Rosenthal syndrome (MRS) is a rare disorder of unknown cause. The classical triad of MRS is orofacial edema, recurrent facial paralysis, and a fissured tongue. Patient: We present a 9-year-old girl with a recurrent peripheral facial paralysis. She experienced the first episode of a peripheral facial paralysis on the same side without orofacial swelling and lingua plicata 1 year ago. She was diagnosed with Hashimoto thyroiditis 9 months earlier, as confirmed by an endocrinologic investigation. Results: While the patient was hospitalized with recurrent facial paralysis, we found that serum levels of free thyroxine (1.3 ng/dL) and thyrotropin (0.4 uIU/mL) were within normal range, but the level of antithyroperoxidase antibodies (772.0 IU/mL) was very increased. She had been taking an oral prednisolone orally for 2 weeks. At the 1-month follow-up, the patient’s symptoms had completely disappeared. Discussion: The possible correlation between MRS and autoimmune disorders has been documented in only one report, which described an adult with autoimmune thyroiditis (Hashimoto thyroiditis) and MRS. We suggest that the co-occurrence of MRS and Hashimoto thyroiditis is not coincidental but linked to autoimmunity. [Copyright &y& Elsevier]

Aims: The aim of this study was to perform a 5α-reductase type 2 gene (SRD5A2) analysis in 6 Korean patients with external genitalia ranging from predominantly female to male in whom 5α-reductase type 2 deficiency was suspected. Patients: Six patients from five unrelated families participated, and all of their parents were non-consanguineous. Three patients presented with ambiguous genitalia at birth, and 2 were referred owing to delayed puberty. The other patient was presented incidentally during an operation for inguinal hernia. Basal and post-human chorionic gonadotropin-stimulated serum testosterone and dihydrotestosterone levels were determined, but neither the levels nor ratio yielded enough information for differential diagnosis. Confirmative diagnosis was achieved by SRD5A2 gene analysis. Results: Four different pathologic mutations were identified. All have already been reported, and are located in exon 1 (p.Q6X), exon 4 (p.G203S and c.655delT), and exon 5 (p.R246Q). p.R246Q was the most frequently identified mutation in our study, and c.655delT has been detected only in Korean patients to date. Conclusion: The molecular analysis is the most reliable method for a correct diagnosis of 5α-reductase type 2 deficiency. Identification of mutations also enables genetic counseling for families at risk. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background Ornithine transcarbamylase deficiency, an inborn error of metabolism, is the most common urea cycle disorder and is caused by mutations in the OTC gene located on Xp21. In this study, the clinical and genetic characteristics of seven Korean patients with ornithine transcarbamylase deficiency were analyzed. Methods During 2009-2012, a total of seven patients (three male and four female patients) from six unrelated families were diagnosed with ornithine transcarbamylase deficiency by biochemical or molecular analysis. OTC gene sequencing analysis was performed in six of these patients. Clinical manifestations, clinical courses, and the results of genetic studies were reviewed retrospectively. Results The median follow-up period for the seven patients with ornithine transcarbamylase deficiency was 44 months (11.9-150 months). Clinical manifestations of ornithine transcarbamylase deficiency included vomiting and seizure, which were the most frequent signs at admission. Two of the four heterozygous female patients (50%) experienced severe neurological sequelae. The early onset male patient characterized severe neurological deficits. The late-onset male patient recovered completely from acute encephalopathy and coma without any neurological deficits. Direct sequencing and multiplex ligation-dependent probe amplification analysis of OTC gene revealed five different mutations. Of these mutations, two were novel (c.867-3T>C and c.664_667delinsAC). Conclusions Ornithine transcarbamylase deficiency was genetically heterogeneous in the seven Korean patients with confirmed ornithine transcarbamylase deficiency diagnosis by biochemical findings and/or genetic analysis, together with two novel mutations in the OTC gene. We hope that these data will contribute to a better understanding of the clinical course and distinct molecular genetic characteristics of Korean patients with ornithine transcarbamylase deficiency. [ABSTRACT FROM AUTHOR]